Add ImGui Manager to manage creation and deletion of contexts

scwx-qt/source/scwx/qt/manager/imgui_manager.cpp

@@ -0,0 +1,92 @@
+#include <scwx/qt/manager/imgui_manager.hpp>
+#include <scwx/util/logger.hpp>
+
+#include <imgui.h>
+
+namespace scwx
+{
+namespace qt
+{
+namespace manager
+{
+
+static const std::string logPrefix_ = "scwx::qt::manager::imgui_manager";
+static const auto        logger_    = scwx::util::Logger::Create(logPrefix_);
+
+class ImGuiManagerImpl
+{
+public:
+   explicit ImGuiManagerImpl() {}
+
+   ~ImGuiManagerImpl() = default;
+
+   std::vector<ImGuiContextInfo> contexts_ {};
+};
+
+ImGuiManager::ImGuiManager() :
+    QObject(nullptr), p {std::make_unique<ImGuiManagerImpl>()}
+{
+}
+
+ImGuiManager::~ImGuiManager() {}
+
+ImGuiContext* ImGuiManager::CreateContext(const std::string& name)
+{
+   ImGuiContext* context = ImGui::CreateContext();
+   ImGui::SetCurrentContext(context);
+
+   // ImGui Configuration
+   auto& io = ImGui::GetIO();
+
+   // Disable automatic configuration loading/saving
+   io.IniFilename = nullptr;
+
+   // Style
+   auto& style         = ImGui::GetStyle();
+   style.WindowMinSize = {10.0f, 10.0f};
+
+   // Register context
+   static size_t nextId_ {0};
+   p->contexts_.emplace_back(ImGuiContextInfo {nextId_++, name, context});
+
+   // Inform observers contexts have been updated
+   emit ContextsUpdated();
+
+   return context;
+}
+
+void ImGuiManager::DestroyContext(const std::string& name)
+{
+   // Find context from registry
+   auto it = std::find_if(p->contexts_.begin(),
+                          p->contexts_.end(),
+                          [&](auto& info) { return info.name_ == name; });
+
+   if (it != p->contexts_.end())
+   {
+      // Destroy context and erase from index
+      ImGui::SetCurrentContext(it->context_);
+      ImGui::DestroyContext();
+      p->contexts_.erase(it);
+
+      // Inform observers contexts have been updated
+      emit ContextsUpdated();
+   }
+}
+
+std::vector<ImGuiContextInfo> ImGuiManager::contexts() const
+{
+   return p->contexts_;
+}
+
+ImGuiManager& ImGuiManager::Instance()
+{
+   static ImGuiManager instance_;
+   return instance_;
+}
+
+bool ImGuiContextInfo::operator==(const ImGuiContextInfo& o) const = default;
+
+} // namespace manager
+} // namespace qt
+} // namespace scwx

scwx-qt/source/scwx/qt/manager/imgui_manager.hpp

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <memory>
+#include <string>
+
+#include <QObject>
+
+struct ImGuiContext;
+
+namespace scwx
+{
+namespace qt
+{
+namespace manager
+{
+
+class ImGuiManagerImpl;
+
+struct ImGuiContextInfo
+{
+   size_t        id_ {};
+   std::string   name_ {};
+   ImGuiContext* context_ {};
+
+   bool operator==(const ImGuiContextInfo& o) const;
+};
+
+class ImGuiManager : public QObject
+{
+private:
+   Q_OBJECT
+   Q_DISABLE_COPY(ImGuiManager)
+
+public:
+   explicit ImGuiManager();
+   ~ImGuiManager();
+
+   ImGuiContext* CreateContext(const std::string& name);
+   void          DestroyContext(const std::string& name);
+
+   std::vector<ImGuiContextInfo> contexts() const;
+
+   static ImGuiManager& Instance();
+
+signals:
+   void ContextsUpdated();
+
+private:
+   friend class ImGuiManagerImpl;
+   std::unique_ptr<ImGuiManagerImpl> p;
+};
+
+} // namespace manager
+} // namespace qt
+} // namespace scwx